Question

the 11th term of an ap -5, -5/2, 0, 5/2.....is
a.-20
b.20
c.-30
d.30
please answer step by step.....answer if u know only plssssssssss
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Answer 1

Answer:

70

Step-by-step explanation:

Given,

A.P : - 5, 5 / 2, 0, 5 / 2,..............

a = - 5

d = ( 5 / 2 ) - ( - 5 )

  = ( 5 / 2 ) + 5

  = ( 5 / 2 ) + ( 10 / 2 )

  = ( 5 + 10 ) / 2

  = 15 / 2

d = 7.5

11th term is t11.

t11 = a + 10d

    = - 5 + 10 ( 7.5 )

    = - 5 + 75

    = 75 - 5

t11 = 70

Answer 2

GiveN :-

• First term = - 5

• Common difference = - 5/2 - ( - 5 ) = 5/2

• Number of terms = 11

To FinD :-

• 11th term of the given A.P

SolutioN :-

By using A.P formula :

$\large:\implies \boxed{\bf \blue{ A_n = a + ( n-1)d}} \\ \\:\implies \sf A_{11} = - 5 + (11 - 1) \times \frac{5}{2} \\ \\:\implies \sf A_{11} = - 5 + 10 \times \frac{5}{2} \\ \\:\implies \sf A_{11} = - 5 + 5 \times 5 \\ \\:\implies \sf A_{11} = - 5 + 25 \\ \\ :\implies \boxed{ \sf A_{11} = 20}$

$\large \therefore \underline {\bf \green{11th \: term \: of \: AP \: is \: 20}}$